Sarah Jane considers the names "Harry" and "Alistair" for the Archetype before settling on Luke. She is referring to the characters Brigadier Alistair Gordon Lethbridge-Stewart and Harry Sullivan, close friends of hers during the time she spent travelling with the Doctor. They were played by Nicholas Courtney and Ian Marter in Doctor Who (1963) respectively

This episode takes place approximately a year and a half after the events of the 2006 Doctor Who episode "School Reunion"

Among the items seen in Sarah Jane's attic are a 1970s photograph of Nicholas Courtney as his Doctor Who character Brigadier Alistair Gordon Lethbridge-Stewart, a promotional photo of Elisabeth Sladen, K-9 and a dog from the short-lived K-9 and Company and a production sketch of a Dalek for Doctor Who (2005).

The alien poet that Sarah Jane (Elisabeth Sladen) sends to her home planet, Archetine V, is the same species as "Mary", as seen in the 2006 Torchwood episode "Greeks Bearing Gifts".

Sarah Jane: Maria, there's two kinds of people in this world: people who panic and....then there's us. Got it?
Maria: Got it.

Mrs. Wormwood: (to Sarah Jane) In the language of your young ones, bring...it...on.

Mrs. Wormwood: Until we meet again...Ms. Smith.

Sarah Jane: I saw amazing things, out there in space...but there is strangeness to be found, wherever you turn. Life on Earth can be an adventure too...you just need to know where to look.

Maria: How would you know if you were going mad?
Alan: Ask you mother, she's the expert.
Maria: I'm gonna tell her you said that!

The Archetype (Luke): Hello, Maria, hello screaming girl.

Sarah Jane: I met this man, a very special man, called the Doctor. And years ago, we travelled together.
Maria: In space?
Sarah Jane: Space and time. Then it came to an end. Suddenly, I was back to a normal life. Electric bills, burst pipes, bus tickets...and rain.
Kelsey: She's gone completely loop-the-loop!
Sarah Jane: There, y'see? Who could I talk to about it? For years I tried to forget! And then I met him again, the Doctor...but we had both changed, but it was funny because we were still both the same. I learned, that I could carry on here on Earth, doing what we always did.

Maria: I never asked...have you got a boyfriend or...?
Sarah Jane: Well, there was only ever one man for me, and after him...nothing compared.

Sarah Jane: (to Maria) When I was your age, I used to think "Oh, when I'm grown up, I'll know what I want, I'll be sorted." But you never really know what you want. You never feel grown up, not really. You never sort it all out...so I thought, I could handle life on my own. But after today...I don't want to!